package com.itheima.reggie.controller;

import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.UUID;

/**
 * @BelongsProject: reggie_take_out
 * @BelongsPackage: com.itheima.reggie.controller
 * @Author: song
 * @CreateTime: 2022-06-15  00:07
 * @Description: 文件上传和下载
 * @Version: 1.0
 */
@Slf4j
@RestController
@RequestMapping("/common")
public class CommonController {

    @Value("${reggie.path}")
    private String basePath;

    @PostMapping("/upload")
    public R<String> upload(MultipartFile file){

        // 原始文件名
        String filename = file.getOriginalFilename();
        String suffix = filename.substring(filename.lastIndexOf("."));
        // 使用UUID重新生成文件名，防止文件名重复！
        String newFileName = UUID.randomUUID().toString() + suffix;
        // 创建一个目录对象
        File dir = new File(basePath);
        // 判断文件夹是否存在，不存在则创建！
        if (!dir.exists()){
            dir.mkdirs();
        }
        try {
            // 将临时文件转存到指定位置
            file.transferTo(new File(basePath + newFileName));
        } catch (IOException e) {
            e.printStackTrace();
        }

        return R.success(newFileName);
    }

    /**
     * @description: 文件下载
     * @author: song
     * @date: 2022/6/19 9:35
     * @param: [name, response]
     * @return: void
     **/
    @GetMapping("/download")
    public void downLoad(String name, HttpServletResponse response){

        try {
            // 输入流 读取文件内容
            FileInputStream fileInputStream = new FileInputStream(new File(basePath + name));
            // 输出流，通过输出流将文件歇会浏览器，在浏览器显示
            ServletOutputStream outputStream = response.getOutputStream();

            response.setContentType("image/jpeg");

            int len = 0;
            byte[] bytes = new byte[1024];
            while((len = fileInputStream.read(bytes)) != -1){
                outputStream.write(bytes,0,len);
                outputStream.flush();
            }
            // 关闭输入输出流
            outputStream.close();
            fileInputStream.close();
        } catch (Exception e) {
            e.printStackTrace();
        }

    }
}
